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GLSL Vertex Shader error


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#1 Madd   Members   -  Reputation: 151

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Posted 30 August 2012 - 03:47 PM

Hello, I get an error while compiling my vertex shader. Here is the code for my shader:

/*
MaddEngine.vert
GLSL vertex shader used by Madd Engine
*/
void main()
{
  gl_TexCoord[0] = gl_MultiTexCoord0;
  gl_Position = gl_ProjectionMatrix * gl_ModelViewMatrix * gl_Vertex;
}

When I run my application, it outputs the InfoLog to a file, here it is:

Vertex info
-----------
(0) : error C0000: syntax error, unexpected $end at token "<EOF>"
(0) : error C0501: type name expected at token "<null atom>"

The same error occurs even if I comment out the entire shader code. Does anyone know where the problem is?

P.S. The fragment shader works as it should, here is the code:

/*
MaddEngine.frag
GLSL fragment shader used by Madd Engine
*/
uniform sampler2D tex;
void main()
{
  vec4 texel = texture2D(tex, gl_TexCoord[0].st);
  gl_FragColor = gl_Color * texel;
}

Edited by Madd, 30 August 2012 - 03:48 PM.


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#2 Sponji   Members   -  Reputation: 1007

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Posted 30 August 2012 - 07:38 PM

Is the loading code different for vertex shader? Feels like you have messed up something there.
Derp

#3 BitMaster   Crossbones+   -  Reputation: 3006

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Posted 31 August 2012 - 12:41 AM

Is it possible you have invalid characters in the file? Depending on the editor an invalid character can easily slip with a copy'n'paste or accidental hotkey. A lot of editors will then pick a suitable encoding to encode the undesired character and it will often be invisble to the naked eye then.
Have you tried explicitely forcing ANSI encoding on the file (for example in Notepad++ Encoding->Convert to ANSI)? If the problem is a rogue character it will usually show up in an obvious way (the not-in-font symbol or 'weird' symbols).

#4 Madd   Members   -  Reputation: 151

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Posted 31 August 2012 - 03:40 AM

Here's the code for the loader:

[source lang="cpp"]void meEnableShaders(){ /* load the fragment shader */ char *frag_buffer, *vert_buffer; FILE *fp = fopen("MaddEngine.frag", "rb"); int frag_size; fseek(fp, 0, SEEK_END); frag_size = ftell(fp); fseek(fp, 0, SEEK_SET); frag_buffer = (char*)malloc(frag_size); fread(frag_buffer, 1, frag_size, fp); fclose(fp); /* load the vertex shader */ fp = fopen("MaddEngine.vert", "rb"); int vert_size; fseek(fp, 0, SEEK_END); vert_size = ftell(fp); vert_buffer = (char*)malloc(vert_size); fread(vert_buffer, 1, vert_size, fp); fclose(fp);#ifdef ARB_SHADER me_fragment_shader = glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB); glShaderSourceARB(me_fragment_shader, 1, &frag_buffer, &frag_size); glCompileShaderARB(me_fragment_shader); me_vertex_shader = glCreateShaderObjectARB(GL_VERTEX_SHADER_ARB); glShaderSourceARB(me_vertex_shader, 1, &vert_buffer, &vert_size); glCompileShaderARB(me_vertex_shader); me_shader_program = glCreateProgramObjectARB(); glAttachObjectARB(me_shader_program, me_fragment_shader); glAttachObjectARB(me_shader_program, me_vertex_shader); glLinkProgramARB(me_shader_program); glUseProgramObjectARB(me_shader_program);#else me_fragment_shader = glCreateShader(GL_FRAGMENT_SHADER); glShaderSource(me_fragment_shader, 1, &frag_buffer, &frag_size); glCompileShader(me_fragment_shader); me_vertex_shader = glCreateShader(GL_VERTEX_SHADER); glShaderSource(me_vertex_shader, 1, &vert_buffer, &vert_size); glCompileShader(me_vertex_shader); me_shader_program = glCreateProgram(); glAttachShader(me_shader_program, me_fragment_shader); glAttachShader(me_shader_program, me_vertex_shader); glLinkProgram(me_shader_program); glUseProgram(me_shader_program);#endif free(frag_buffer); free(vert_buffer);};[/source]


It is compiled without the ARB_SHADER macro (so it uses the standard OpenGL functions).

I edit the files with gedit under Ubuntu, which uses UTF-8.

Edited by Madd, 31 August 2012 - 03:42 AM.


#5 Madd   Members   -  Reputation: 151

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Posted 31 August 2012 - 03:43 AM

I'm sorry, I just noticed the problem. I forgot to seek back to the start of the file after getting its size *facepalm*

#6 L. Spiro   Crossbones+   -  Reputation: 9732

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Posted 31 August 2012 - 05:05 AM

After setting the stream to the end of the file and calling ::ftell(), you never set the stream back to the beginning of the file before you try to read it.
On the vertex shader.


L. Spiro


[EDIT]
I stopped reading as soon as I saw the problem. Even if it was just one last post with a single sentence explaining the solution.
[/EDIT]

Edited by L. Spiro, 31 August 2012 - 05:06 AM.

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#7 V-man   Members   -  Reputation: 797

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Posted 02 September 2012 - 05:26 AM

Even if the problem has been found, it isn't a good idea to read a text file as binary because on some systems (Windows), end of lines are in the form of \r\n or was it \n\r.
It is better to open the file this way
FILE *fp = fopen("MaddEngine.frag", "r"); //changed the "rb" to "r"

and the library will automatically convert all the \r\n to \n (newlines).

and it is a good idea to NULL terminate the file string yourself.
Sig: http://glhlib.sourceforge.net
an open source GLU replacement library. Much more modern than GLU.
float matrix[16], inverse_matrix[16];
glhLoadIdentityf2(matrix);
glhTranslatef2(matrix, 0.0, 0.0, 5.0);
glhRotateAboutXf2(matrix, angleInRadians);
glhScalef2(matrix, 1.0, 1.0, -1.0);
glhQuickInvertMatrixf2(matrix, inverse_matrix);
glUniformMatrix4fv(uniformLocation1, 1, FALSE, matrix);
glUniformMatrix4fv(uniformLocation2, 1, FALSE, inverse_matrix);




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